Prdm13 is required for Ebf3+ amacrine cell formation in the retina.

Amacrine interneurons play a critical role in the processing of visual signals within the retina. They are highly diverse, representing 30 or more distinct subtypes. Little is known about how amacrine subtypes acquire their unique gene expression and morphological features. We characterized the gene expression pattern of the zinc-finger transcription factor Prdm13 in the mouse. Consistent with a developmental role, Prdm13 was expressed by Ptf1a+ amacrine and horizontal precursors. Over time, Prdm13 expression diverged from the transiently expressed Ptf1a and marked just a subset of amacrine cells in the adult retina. While heterogeneous, we show that most of these Prdm13+ amacrine cells express the transcription factor Ebf3 and the calcium binding protein calretinin. Loss of Prdm13 did not affect the number of amacrine cells formed during development. However, we observed a modest loss of amacrine cells and increased apoptosis that correlated with the onset timing of Ebf3 expression. Adult Prdm13 loss-of-function mice had 25% fewer amacrine cells, altered calretinin expression, and a lack of Ebf3+ amacrines. Forcing Prdm13 expression in retinal progenitor cells did not significantly increase amacrine cell formation, Ebf3 or calretinin expression, and appeared detrimental to the survival of photoreceptors. Our data show that Prdm13 is not required for amacrine fate as a class, but is essential for the formation of Ebf3+ amacrine cell subtypes. Rather than driving subtype identity, Prdm13 may act by restricting competing fate programs to maintain identity and survival.

Prevalence of Eucoleus garfiai in Wild Boars Hunted at Different Altitudes in the Campania and Latium Regions (Italy).

Recent reports of Eucoleus garfiai in wild boars in southern Italy have highlighted the need for collecting epidemiological data on the presence of this parasite and understanding the role of possible interactions between wild boars, E. garfiai, and the environment. This study analyses, using histopathological and biomolecular techniques, the presence of E. garfiai in tongue samples of wild boars hunted in four provinces of the Campania and Latium regions (Italy), in areas located above and below 900 m above sea level (asl). Histopathological examinations revealed the presence of adults and eggs of nematodes, which were subsequently identified as E. garfiai by biomolecular analysis, in the tongue epithelium. The detection of the parasite was more frequent in samples collected from hunting areas located above 900 m asl than in those collected from areas located below 900 m asl (66.67% vs. 38.09%; p < 0.01). Some species of earthworms are intermediate hosts of E. garfiai and it is well known that earthworms are more present in high quality soils. Therefore, we can suggest that the higher prevalence of E. garfiai at higher altitudes is probably linked to a greater presence of earthworms in the soil, due to its higher quality in these areas.

Does having a cat in your house increase your risk of catching COVID-19?

Due to the zoonotic origin of SARS-Coronavirus 2 (SARS-CoV-2), the potential for its transmission from humans back to animals and the possibility that it might establish ongoing infection pathways in other animal species has been discussed. Cats are highly susceptible to SARS-CoV-2 and were shown experimentally to transmit the virus to other cats. Infection of cats has been widely reported. Domestic cats in COVID-19-positive households could therefore be a part of a human to animal to human transmission pathway. Here, we report the results of a qualitative risk assessment focusing on the potential of cat to human transmission in such settings. The assessment was based on evidence available by October 2021. After the introduction of SARS-CoV-2 to a household by a human, cats may become infected and infected cats may pose an additional infection risk for other members of the household. In order to assess this additional risk qualitatively, expert opinion was elicited within the framework of a modified Delphi procedure. The conclusion was that the additional risk of infection of an additional person in a household associated with keeping a domestic cat is very low to negligible, depending on the intensity of cat-to-human interactions. The separation of cats from humans suffering from SARS-CoV-2 infection should contribute to preventing further transmission.

Management Models Applied to the Human-Wolf Conflict in Agro-Forestry-Pastoral Territories of Two Italian Protected Areas and One Spanish Game Area.

Our work shows that, despite the persistence of persecutory actions, conservation activity has proved successful for the return of numerous wild mammals to different habitats, including the wolf. The human-wolf conflict is still described in all countries where the wolf is present. This is evidenced by the high number of damages on livestock, and the corpses of wolves found both in protected areas and in those where hunting is permitted. The diagnosis of road accidents, together with poisoning and poaching, are major causes of mortality. Although hunting records the highest percentage of kills in Spain, the demographic stability reported by the censuses suggests that this activity does not have a consistent influence on the Iberian wolf population's survival. In Italy, where wolf hunting is prohibited, wolf populations are to be increasing. In some Italian situations, wolf attacks on horses seem to cause unwanted damage to foals, but they represent a very precious source of information about the habits of carnivores. A simple management plan would be sufficient to help the coexistence between the productive parts and the ecosystem services ensured by the presence of the wolf. The presence of hybrids is a negative factor.

Role of Rapid Antigen Testing in Population-Based SARS-CoV-2 Screening.

This study evaluates a population-based screening of asymptomatic people, using a rapid antigen diagnostic test (RADT), in areas of high transmission. To detect sources of SARS-CoV-2 infection, nasopharyngeal samples were taken and were tested using RADT. Confirmatory RT-qPCR tests were performed in both positive and negative cases. The internal validity of the RADT, the prevalence of infection, and the positive and negative predictive values (PPV and NPV) were estimated, based on the percentages of confirmed cases with 95% confidence interval. Of the 157,920 people registered, 50,492 participated in the screening; 50,052 were negative, and 440 were positive on the RADT (0.87%). A total of 221 positive RADT samples were reanalysed using RT-qPCR and 214 were confirmed as positive (96.8%; 95% CI: 93.5-98.7%), while 657 out of 660 negative RADT samples were confirmed as RT-qPCR negative (99.5%; 95% CI 98.7-99.9%). The sensitivity obtained was 65.1% (38.4-90.2%) and the specificity was 99.97% (99.94-99.99%). The prevalence of infection was 1.30% (0.95-2.13%). The PPVs were 95.4% (85.9-98.9%) and 97.9% (93.3-99.5%), respectively, while the NPVs were 99.7% (99.4-100%) and 99.2% (98.7-100%), respectively. The high specificity found allow us to report a high screening performance in asymptomatic patients, even in areas where the prevalence of infection was less than 2%.

Prevalence study of the lungworm Aelurostrongylus abstrusus in stray cats of Portugal.

In this study we have investigated the prevalence of aelurostrongylosis, one of the most common feline pulmonary parasitic diseases, in cats from the north-west region of Portugal. For this purpose, 97 faecal samples were collected from cats at risk of being infected by Aelurostrongylus abstrusus in an animal shelter and in a municipal facility. Using the Baermann-Wetzel coprological technique, faecal shedding of first stage larvae (L1) was detected in 17.4% of the cats. Based on this result, it can be concluded that this lungworm infection seems to be common among feral cats in the north-west region of Portugal, in spite of the fact that clinical aelurostrongylosis is not frequently diagnosed by feline practitioners in the area. This parasitic disease should be included in the differential diagnosis of cats presenting with coughing or dyspnoea, and it also should be extended to asymptomatic animals with pulmonary nodules detected by image diagnosis.

Repression by PRDM13 is critical for generating precision in neuronal identity.

The mechanisms that activate some genes while silencing others are critical to ensure precision in lineage specification as multipotent progenitors become restricted in cell fate. During neurodevelopment, these mechanisms are required to generate the diversity of neuronal subtypes found in the nervous system. Here we report interactions between basic helix-loop-helix (bHLH) transcriptional activators and the transcriptional repressor PRDM13 that are critical for specifying dorsal spinal cord neurons. PRDM13 inhibits gene expression programs for excitatory neuronal lineages in the dorsal neural tube. Strikingly, PRDM13 also ensures a battery of ventral neural tube specification genes such as Olig1, Olig2 and Prdm12 are excluded dorsally. PRDM13 does this via recruitment to chromatin by multiple neural bHLH factors to restrict gene expression in specific neuronal lineages. Together these findings highlight the function of PRDM13 in repressing the activity of bHLH transcriptional activators that together are required to achieve precise neuronal specification during mouse development.